The present invention is in the field of braking systems. More specifically this invention relates to the brake linings for use in a braking disk.
Modern steel brake designs rely on the friction generated between solid steel and sintered metal wear surfaces. The steel surface may take the form of a full annular disk, or may be segmented and connected, with or without a substructure, to form a full annular disk. The sintered metal components are lower in strength, and may be applied directly to an annular disk, or segmented and mounted to an annular disk substructure or lining carrier.
Segmented linings contain a number of consumable lining containers or cups which are fastened to a reusable carrier. The cups are typically stamped from steel sheet metal and are formed to hold or contain the lining material. The cups are usually plated to protect against corrosion, and to aid in developing a metallurgical bond with the lining material. Powdered metal is then added to the lining cup through the conventional process of densification and sintering.
Brake wear is effected by, among other things, the ratio of energy absorbed per unit of lining surface area (lining loading). Due to the porosity of powdered metal material, linings also act as good insulators. As a result of this, energy, in the form of heat, is slow to transfer through the lining material. Large thermal gradients therefore develop through the thickness of the cup. Due to differential thermal expansion, the lining cup deforms such that the area at the wear interface is reduced. This results in a reduction in “effective” lining area, high localized lining loadings and subsequently increased wear.
A method of attachment of the lining cups and material is desired which would increase the “effective” lining wear area, even after sustained use.